Fauna
Invertebrate

European Green Crab

Carcinus maenas

Also known as Shore Crab, Green Shore Crab, European Shore Crab

European green crabs are opportunistic predators capable of surviving extreme shifts in salinity and temperature. Distinguished by five sharp teeth flanking each eye, these hardy crustaceans dig into soft substrate and shelter beneath rocks to ambush young clams and mussels. Their extraordinary adaptability has allowed them to establish voracious invasive populations along coastal estuaries worldwide.

InvasiveCoastalCrustacean
European Green Crab reference1 / 7
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Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Key facts
Diet & preyMussels, Clams, Oysters
Predators
  • Gulls
  • Large fish
  • Sea otters
ThreatsEradication programs in introduced regions and predation by larger marine life
HabitatsIntertidal zones, estuaries, salt marshes, and shallow bays
Life span4–7 years
Classification
  1. OrderDecapoda
  2. FamilyCarcinidae
  3. GenusCarcinus
  4. SpeciesCarcinus maenas
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Pinchers can deliver a painful nip; handle carefully by the rear of the carapace.
Why it is dangerous
Equipped with strong chelae (claws) capable of inflicting painful nips and breaking human skin when handled.
How to recognize a risky encounter
Look for a fan-shaped carapace with five prominent lateral teeth on each side of the eyes.
What to do
Grasp the crab firmly from behind the shell; never place fingers near the front claws.
Responsible observation
  • Safe Handling: Pick up from behind the shell between thumb and forefinger to avoid claws.
  • Reporting Invasives: Document sightings with photos and location data in non-native coastal regions.
  • Tidepool Observation: Gently lift loose rocks at low tide and return them to their original positions.
Related species
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